Acoustical instrument



April 26, 1932. MALDEN 1 8 5,

ACOUSTI CAL INSTRUMENT Filed April 7, 1927 3 Sheets-Sheet l N Hi tINVENTOR.

April 26, 1932. M. ALDEN 1,855,933

ACOUSTI CAL INSTRUMENT M. ALDEN ACOUSTICAL INSTRUMENT April 26, 1932.

Filed April 7, 1927 3 Sheets- Sheet 3 x H or f ia I Patented 26, 1 932UNITED STATES PAT T OFFICE MILTOLT ALDEN, OF SPRINGFIELD,AMASSACHUSETTS,ASSIGNOR, BY MESNE ASSIGN- MENTS, T RADIO INVENTIONS, INC.', .A.CORPORATIDN OF NEW YORK Acous'rIoaL INSTRUMENT Application filed April7, 1927. Serial no. 131,754.

I The one object of my invention is to produce a radio broadcastreceiver in combination with an electrical quality. O

Another object is to produce a combination as described above from whichthe radiotuning elements and their associated component phonograph ofhigh parts may be removed as a unit in'order that theprogram to bereceived may be controlled from.a distance.

. Still another object is to produce an apparatus of the type describedhaving extremely high tonal quality both in respect to the reproductionof mechanical records and the reproduction of radio broadcasts.

My invention consists chiefly of the combination of turntableelectrically driven by the type of motor frequently employed inalternating current integrating watt-meters, a governor, and a stylusoperated magnetic pick-up associated therewith, a high quality amplifierfor use for the reproduct on ofboth records and broadcasting, ahighgrade loud speak r' which may be of the cone type,. -2 a removab'container carrying the tuning elements and their associated apparatus,and

suitable energizing sources for thefradio apparatus all contained in onecabinet.

J I thus produce a unit in which many of the component parts are usedboth for radio reproduction and for record reproduction therebyconsiderably lowering the manufacturing cost, and due to the removablefeature of the tuning element, the operation of the device as a radioreceiver may be con-' trolled from a distance.

7 part of the turntable.

lly sectional front view Referring to the drawings, Fig. 1 isaperspective view of one embodiment of my invention, showing the radiocontrol box removed from the cabinet; Fig. 2 is a detail of a part ofthe phonograp mechanism. e j

' Fig. 2a.is a perspective view of certain -modified details. 1 v

Fig. 3 is an elevation o f.the motor and a Fig. 4 is a partia with thecone of the speaker removed.

Fig. 5 is a partially-sectional side view of the apparatus.

' Fig. 6 is a schematic wiring diagram showing one of many possiblearrangements of the transfer switch.

The cabinet-10 may be of any suitable design and provided with a numberof chambers or compartments One may preferably be furnished with a loudspeaker having a rill or outlet 11 at one side. An upper chamer has ahingedcover 12. The cabinet may also be provlded with an inner cldsure13 having a recess or compartment 14- adapted to hold the tuning box 15so that its panel 16 will be substantlally flush with the closure -13.Upon a shelf 17 in acentral compartment having adoor 12' may be mountedan audio frequency amplifier 18 which may preferably be of the typedisclosed in my Patent 1,678,717. A chamber may be provided' in thebottom of the cabinet 10 for the power sources for the vacuum tubesused, here indicated as the cathode'heating battery 19 and the anodesupply batteries 20 and 21,

but it should be understood that battery eliminators, motor generators,or other means of .power supply may be employed.

Theloud speaker movement 22 may be secured. to thewall 23 of the recessor well 14 and itscone-like diaphragm 22' may. be securleid 1to orbehind the outer edge of the gm 1 The turntable 24, which is preferablyconst-ructed of aluminum, is mounted in the central cpmpartment upon thehorizontal shaft 25 and this shaft may be provided with spring memberssuch as 26 and 27 forfricti'onally engaging the'central aperture of therecord 28 and holding it in place.

The disc 24 is somewhat larger than the largest record to be used andits free edge passes between the pole ti s 29, 30, 31, 32 and 33 of theedd current in uction motor drive until 34 whic ma be suitably mountedwith- 5 The end of this bar when in playing position engages with thespring clips 39 and 40. This bar carries the carriage 41 which may besupported from the bar by grooved rollers 42 and 43 allowing it to moveeasily along the bar 37 and to swingabout this bar. De-

pending froin the carriage 41 is the stylus op-' erated magnetic pick-up44 which should be so balanced and mounted as to cause the st lus 45 toengage the grooves of the recor 28 with proper pressure. This pick-upmaybe of any suitable type such as that disclosed in my Patent1,756,966.

The tuning box 15 is attached to the cabinet 10 by a flexible cable 46which contains all necessary leads such as antenna, ground, battery anddetector out-put leads. Of course this cable may be wound on a suitablereel. This tuning box may contain suitable radio frequency amplificationand detection apparatus 51 and 52 respectively with their tuning andvolume control devices which may be of any suitable type. I have shown avolume control at 47, adetector rheostat at 48 and as a tuning control,indicated at 49, I prefer to use the localized control disclosed in mycopendng applications #154,689, filed Dec. 14, 1926, or 163,196 filedJan..24, 1927.

A plate battery 53 is provided for the detector. I

A switch is provided having threepositions. In the central position allcurrent is turned ofi. In the phonograph operating position the tubes ofthe audio frequency am-. pli'fier are lighted and the alternatingcurrent house line 60 is connected s'uitablyto the disc drivin magnet34. In the radio operating position all the tubes in the apparatus arelit and the driving magnets 34 are disconnected. This switch alsoeffects the connection of the in-put of the audio frequency amplifier toeither the detector output or the out-putof the magnetic pick-up44 apropriately.

' n operation as a-phonograph, the bar 37 is disengaged from its clips39 and 40, and is swung horizontally outward until arecord such as 28can be conveniently snapped on to the shaft 25 so as, to be held againstthe turntable 24 by the springs as 26 and 27. The rod 37 is then swungback to engage the spring clips 39 and 40. The'magnetic pick-up 44 israised from the record 28 and moved along the bar 37 until the stylus 45is-opposite the outer grooves of the record. The switch 50 is thenadjusted tothe phonograph position thus connecting the input of theaudio frequency amplifier 18 to .the pick-up 44, connecting the motor 34to the alternating current lines and lighting the filaments ofthe tubesof the amplifier 18. When used as a radio receiver the switch 50 isplaced in the radio position, thus disconnecting the motor 34, lightingthe tubes of emmas both the amplifier 18 and the control unit 15 andtransferring the input of the audio frequency amplifier 18 from thepick-up 44 to the detector out-put of the radio frequency tuning unit. 1

In Fig. 2a I have shown certain modifications of details which are ofconsiderable value. In this case, I have shown the guide rod 37 mountedbehind the turntable or record holder 24. The pickup device 44 issupported by a sort of gooseneck carriage 41 which travels on this rod37' so that the goose-neck extends around the edge of the record holder.Preferably, this guide rod 37 is inclined somewhat so that gravity mayassist the movement of the pick-up in the grooves in the face of therecord.

In some of the modern records the grooves are made extremely fine andconsequently they are poorly adapted to the feed ofthe needle of thepickup. The inclination of the guide track serves to provide acontinual,

tendency for the pick-up to move towards the center of the record, thuspreventing the needle from jumping out of the groove. It has been foundthat records which cannot be played on the usual horizontal turntable onaccount of this tendency of the needle to jump from the groove, can bevery well played on the vertical turntable of my invention.

In Fig. 2a, I have also shown the motor 34 and the governor 36' bothmounted on a casting or frame 35' which serves tosupport the turntableshaft 25.' This arrangement facilitates construction and installation ofthe parts. I

The vertical record arrangement has an additional advantage in that itdoes not tend to collect dust and grit, which act as abrasives and tendto damage the records when they are 'iised on horizontal planevmachines.

which is not possible with the usual type of swinging support.

The radio receiver with the portable control unit is claimed in myapplication Ser. No. 602.197 filed March 31st, 1932. I

"It should be understood that I do not wish to limit myself to thespecific embodiments of my invention, as shown and described, exceptinsofar as I do limit myself in the following claims.

I'claim:

1.- A combination radio broadcast receiver and phonograph comprising amotor driven phonographrecord holder, an electro-magnetic pick-upcoactin .with a record on the holder, audio ampli ying means connectedto the pick-up, a loud speaker connected to the output of the audioamplifying means,

power supply means for the amplif ing face of sai and coacting with thearmature portion of the turntable for rotating the same, means forsupporting a sound record on saidturntable, a pick-up device providedwith a stylus for coaction with the sound record and means for guidinsaid pick-up device across the record.

. 'Z. A reproducing device com rising a turntable whose plane ofrotation1s inclined more than 45 to the horizontal, means for rotating saidturntable, a pick-up device having a stylus for coaction with a recordsupported on said turntable, a guide rod for said pick-up arranged in a.lane substantially parallel to the lane 0 the turntable but inclined tothe horizontal so that gravity aids the movement of the pick-upalong'said guide rod.

scribed, comprising a metallic turntablemounted on a horizontal axis, aninduction motor stator having pole pieces coacting with both sides ofone edge of the turntable for driving the same, a means for removablysecuring a sound record on said turntable, and a pick-up supported tomove across the face of the record.

3. An instrument of the character described, comprising a turntablemounted on a horizontal axis, a guide rod mounted near said turntable, acarriage having a gooseneck "extension pro ecting around the'edge of the35 turntable, and an electric pickup supported by said gooseneckextension for coaction with the record on said turntable.

4. An instrument of the character described, comprising a-turntablemounted on a horizontal axis, a guide rod mounted adjacent thereto, andinclined downwardly with relation thereto, a carriage mounted to travelon an incline on saidguide rod, and a magnetic pick-up supported by'saidcarriage and adapted to coact with the record on said turntable, wherebygravity assists in. the movement of said pick-up across the face of therecord. Y

consisting of pole pieces and windings arranged on opposite sides of oneedge of said i turntable, agovernor coacting with said turntable and asingle mounting frame supporting said motor, said governor and saidturntable.

6. Asound reproducing instrument comprising a substantiall' verticalturntable mounted on a substan ially horizontal axis' andprovided'witlla metallic armaturepor tion,. an induction motor stator having pole'piecesarranged on. opposite sides of one edge of the metallic armatureportion outside of the-record holding portion of the turntable 8. Acombination radio broadcast receiver and phonograph including a motordriven phonograph record holder, an electric pickup eoacting therewith,a source of electric power, amplifying means and a loud speaker, acabinet containing all of the foregoing elements, a portable controlunit contalning means for controlling the tuning of the receiver andvolume control means and a cable connecting the portable unit and thecabinet and swit ing means for switching the loud speaker from thebroadcast receiver to the hono ra h. p g p MILTON ALDEN.

